Many conventional drug delivery devices that are wearable are limited to only delivering small volumes of a liquid drug to a patient. Other conventional drug delivery devices that can store and deliver larger volumes of a liquid drug to a patient are not designed to be wearable and so are bulky, cumbersome, and uncomfortable when attempted to be worn by a patient. Further, many of these conventional drug delivery devices are not fillable by the patient, thereby limiting their usefulness and longevity.
A need therefore exists for a more compact and lightweight wearable drug delivery device for providing relatively high volumes of a liquid drug to a patient that can be filled by the patient and worn in a comfortable manner.